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          <th colspan="3" align="center">DB_ENV-&gt;close()</th>
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            <h2 class="title" style="clear: both"><a id="envclose"></a>DB_ENV-&gt;close()</h2>
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      <pre class="programlisting">#include &lt;db.h&gt;

int
DB_ENV-&gt;close(DB_ENV *dbenv, u_int32_t flags);  </pre>
      <p>
         The <code class="methodname">DB_ENV-&gt;close()</code> method closes the
         Berkeley DB environment, freeing any allocated resources and
         closing all database handles opened with this environment handle,
         as well as closing any underlying subsystems.
    </p>
      <p>
        When you call the <code class="methodname">DB_ENV-&gt;close()</code> method,
        all open <a class="link" href="db.html" title="Chapter 2.  The DB Handle">DB</a> handles and 
        <a class="link" href="dbc.html" title="Chapter 3.  The DBcursor Handle">DBcursor</a> handles are closed
        automatically by this function. And, when you close a database
        handle, all cursors opened with it are closed automatically.
    </p>
      <p>
       In multiple threads of control, each thread of control opens a
       database environment and the database handles within it. When you
       close each database handle using the
       <code class="methodname">DB_ENV-&gt;close()</code> method, by default, the
       database is not synchronized and is similar to calling the
       <code class="methodname">DB-&gt;close(DB_NOSYNC)</code> method. This is to
       avoid unncessary database synchronization when there are multiple
       environment handles open.  To ensure all open database handles are
       synchronized when you close the last environment handle, set the
       flag parameter value of the <code class="methodname">DB_ENV-&gt;close()</code>
       method to DB_FORCESYNC.  This is similar to calling the
       <code class="methodname">DB-&gt;close(0)</code> method to close each database
       handle. 
    </p>
      <p>
       If a database close operation fails, the method returns a non-zero
       error value for the first instance of such an error, and continues
       to close the rest of the database and environment handles.
    </p>
      <p>
         The <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>  handle should
         not be closed while any other handle that refers to it is not yet
         closed; for example, database environment handles must not be closed
         while transactions in the environment
         have not yet been committed or aborted. Specifically, this includes the
         <a class="link" href="txn.html" title="Chapter 12.  The DB_TXN Handle">DB_TXN</a>, 
         <a class="link" href="logc.html" title="The DB_LOGC Handle">DB_LOGC</a>  and 
         <a class="link" href="memp.html" title="Chapter 8.  The DB_MPOOLFILE Handle">DB_MPOOLFILE</a>  handles.
    </p>
      <p>
         Where the environment was initialized with the 
         <a class="link" href="envopen.html#envopen_DB_INIT_LOCK">DB_INIT_LOCK</a>  flag,
         calling <code class="methodname">DB_ENV-&gt;close()</code> does not release any locks still held by the
         closing process, providing functionality for long-lived locks.
         Processes that want to have all their locks released can do so by
         issuing the appropriate <a class="xref" href="lockvec.html" title="DB_ENV-&gt;lock_vec()">DB_ENV-&gt;lock_vec()</a>  call.
    </p>
      <p>
         Where the environment was initialized with the 
         <a class="link" href="envopen.html#envopen_DB_INIT_MPOOL">DB_INIT_MPOOL</a> flag,
         calling <code class="methodname">DB_ENV-&gt;close()</code> implies calls to 
         <a class="xref" href="mempfclose.html" title="DB_MPOOLFILE-&gt;close()">DB_MPOOLFILE-&gt;close()</a>  for any
         remaining open files in the memory pool that were returned to this
         process by calls to <a class="xref" href="mempfopen.html" title="DB_MPOOLFILE-&gt;open()">DB_MPOOLFILE-&gt;open()</a>.  It does
         not imply a call to <a class="xref" href="mempfsync.html" title="DB_MPOOLFILE-&gt;sync()">DB_MPOOLFILE-&gt;sync()</a>  for those
         files.
    </p>
      <p>
         Where the environment was initialized with the 
         <a class="link" href="envopen.html#envopen_DB_INIT_TXN">DB_INIT_TXN</a>  
         flag, calling <code class="methodname">DB_ENV-&gt;close()</code> aborts any
         unresolved transactions.  Applications should not depend on this
         behavior for transactions involving Berkeley DB databases; all
         such transactions should be explicitly resolved.  The problem with
         depending on this semantic is that aborting an unresolved
         transaction involving database operations requires a database
         handle.  Because the database handles should have been closed
         before calling <code class="methodname">DB_ENV-&gt;close()</code>, it will not
         be possible to abort the transaction, and recovery will have to be
         run on the Berkeley DB environment before further operations are
         done.
    </p>
      <p>
         Where log cursors were created using the 
         <a class="xref" href="logcursor.html" title="DB_ENV-&gt;log_cursor()">DB_ENV-&gt;log_cursor()</a>  method,
         calling <code class="methodname">DB_ENV-&gt;close()</code> does not imply
         closing those cursors.
    </p>
      <p>
         In multithreaded applications, only a single thread may call the
         <code class="methodname">DB_ENV-&gt;close()</code> method.
     </p>
      <p>
         After <code class="methodname">DB_ENV-&gt;close()</code> has been called,
         regardless of its return, the Berkeley DB environment handle may
         not be accessed again.
    </p>
      <p>
         The <code class="methodname">DB_ENV-&gt;close()</code> <span>
            <span>
                  method returns a non-zero error value on failure and 0 on success.
            </span>
            
        </span>
    </p>
      <div class="sect2" lang="en" xml:lang="en">
        <div class="titlepage">
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            <div>
              <h3 class="title"><a id="idp51260384"></a>Parameters</h3>
            </div>
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        <div class="sect3" lang="en" xml:lang="en">
          <div class="titlepage">
            <div>
              <div>
                <h4 class="title"><a id="idp51253848"></a>flags</h4>
              </div>
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          </div>
          <p>
                  The <span class="bold"><strong>flags</strong></span> parameter must be set to 0
                  or be set to the following value:
             </p>
          <div class="itemizedlist">
            <ul type="disc">
              <li>
                <p><a id="dbenvclose_DB_FORCESYNC"></a>
                              <code class="literal">DB_FORCESYNC</code>
                         </p>
                <p>
                            When closing each database handle internally,
                            synchronize the database. If this flag is not
                            specified, the database handle is closed without
                            synchronizing the database.
                        </p>
              </li>
            </ul>
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      <div class="sect2" lang="en" xml:lang="en">
        <div class="titlepage">
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            <div>
              <h3 class="title"><a id="idp51306112"></a>Class</h3>
            </div>
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        <p>
            <a class="link" href="env.html" title="Chapter 5.  The DB_ENV Handle">DB_ENV</a>  
        </p>
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      <div class="sect2" lang="en" xml:lang="en">
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              <h3 class="title"><a id="idp51301256"></a>See Also</h3>
            </div>
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        <p>
             <a class="xref" href="env.html#envlist" title="Database Environments and Related Methods">Database Environments and Related Methods</a> 
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